Make poetry prefer a system-site-package and not update

[truschival]

[x] I have searched the issues and haven't found a duplicate
[x] I have searched discussions and think 1879 could be related because this is what I use.

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Scenario: I have a docker container provided by nvidia, including pytorch (torch 2.2.0a0+6a974be) and python 3.10.12. I want to install my package in the docker image using the available packages as dependency and not update unnesessarily

My stripped-down package now only depends on python = "~3.10" and torch = ">=2.0.1, <3".

I have created a virtual-env with --system-site-packages (and for cargo-cult I also set the flag in POETRY_VIRTUALENVS_OPTIONS_SYSTEM_SITE_PACKAGES=true )

If I list the packages with pip in the virtual environment I see the correct torch version an can use it.
When calling poetry install (without existing lockfile) poetry wants to update torch to 2.5.1.

The available versions match the dependency range of my package, there is no need to update. Why does poetry update, and how can I stop it form updating.

I don't want to restrict the version range of my package because it works on other setups as well with a more recent torch version. I want to avoid installing the recent version in the docker container and rely on the vendors setup.

[truschival]

The current workaround is to build a wheel with poetry build and then rely on pip for installation of said wheel.

I wish for a command line argument of poetry --install that skips unecessary updates e.g. --dont-upgrade